1. Field Of The Invention
The present invention relates generally to an apparatus and method for entering data into a testing system, and more particularly, to an apparatus and method for communicating a testflow description and a binning description to an IC testing system.
2. Related Art
Integrated circuits (IC's) are generally tested during engineering development and during production. Testing is performed by an IC tester such as a Hewlett Packard HP82000 tester, manufactured by Hewlett-Packard Company, Palo Alto, Calif. To perform tests, the testing system requires, among other data, a description of the tests to be performed, a description of the testflow (that is, the order in which and the circumstances under which the tests are to be executed), and a binning description (that is, a description of how to classify the device based on the test results).
There are several conventional techniques for specifying the testflow and binning to the tester. In a first such technique, the testflow and binning are described in a test program which controls the tester. Accordingly, the flow and binning description is embodied in a programming language. A drawback to this is that implementation is difficult because the user must describe the testflow and binning in a language not designed for testing applications and then recompile the test program each time the testflow or binning is changed. This is very time consuming and can be especially burdensome to the user who is generally an IC development engineer for the product being tested rather than a computer programmer.
A further disadvantage of this first approach is that it is difficult to maintain because there must be at least one completely separate test program for each different device to be tested. Accordingly, any time the test methodology changes, all test programs must be rewritten.
In a second conventional approach, the testflow and binning are specified together in a tabular format where tests are specified on one axis and bins on the other. This format limits the flexibility of testflow and binning. It cannot handle more advanced programming constructs such as looping or variables. Furthermore, the table size can become unwieldy as the specification complexity increases.
In a third conventional approach, testflow and binning are specified together using graphical icons. As with the second approach, such a specification cannot represent more advanced programming constructs such as looping or variables.
Therefore, what is needed is an environment for describing testflow and binning in which the test program need not be rewritten for each different test, but which has the flexibility to enable a broad range of testing and binning combinations, and has the power to enable the specification of advanced programming concepts such as looping and variables.